Announced today the release of KDE 4.5, this version comes with many new features and improvements, for example the plasma Desktop received many usability refinements.
The Notification and Job handling workflows have been streamlined. The KDE Applications have been improved in many different areas, the applications have become more powerful, yet easier to use.
For Kubuntu users:
You can upgrade to this new version by using the commands bellow:
1- Add repository
sudo add-apt-repository ppa:kubuntu-ppa/staging
2- Update and upgrade
sudo apt-get update && sudo apt-get upgrade
Useful Links: http://kde.org